1/*
2 * QEMU ETRAX Interrupt Controller.
3 *
4 * Copyright (c) 2008 Edgar E. Iglesias, Axis Communications AB.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25#include "qemu/osdep.h"
26#include "hw/sysbus.h"
27#include "qemu/module.h"
28#include "hw/irq.h"
29#include "hw/qdev-properties.h"
30//#include "pc.h"
31//#include "etraxfs.h"
32
33#define D(x)
34
35#define R_RW_MASK 0
36#define R_R_VECT 1
37#define R_R_MASKED_VECT 2
38#define R_R_NMI 3
39#define R_R_GURU 4
40#define R_MAX 5
41
42#define TYPE_ETRAX_FS_PIC "etraxfs,pic"
43#define ETRAX_FS_PIC(obj) \
44 OBJECT_CHECK(struct etrax_pic, (obj), TYPE_ETRAX_FS_PIC)
45
46struct etrax_pic
47{
48 SysBusDevice parent_obj;
49
50 MemoryRegion mmio;
51 void *interrupt_vector;
52 qemu_irq parent_irq;
53 qemu_irq parent_nmi;
54 uint32_t regs[R_MAX];
55};
56
57static void pic_update(struct etrax_pic *fs)
58{
59 uint32_t vector = 0;
60 int i;
61
62 fs->regs[R_R_MASKED_VECT] = fs->regs[R_R_VECT] & fs->regs[R_RW_MASK];
63
64 /* The ETRAX interrupt controller signals interrupts to the core
65 through an interrupt request wire and an irq vector bus. If
66 multiple interrupts are simultaneously active it chooses vector
67 0x30 and lets the sw choose the priorities. */
68 if (fs->regs[R_R_MASKED_VECT]) {
69 uint32_t mv = fs->regs[R_R_MASKED_VECT];
70 for (i = 0; i < 31; i++) {
71 if (mv & 1) {
72 vector = 0x31 + i;
73 /* Check for multiple interrupts. */
74 if (mv > 1)
75 vector = 0x30;
76 break;
77 }
78 mv >>= 1;
79 }
80 }
81
82 if (fs->interrupt_vector) {
83 /* hack alert: ptr property */
84 *(uint32_t*)(fs->interrupt_vector) = vector;
85 }
86 qemu_set_irq(fs->parent_irq, !!vector);
87}
88
89static uint64_t
90pic_read(void *opaque, hwaddr addr, unsigned int size)
91{
92 struct etrax_pic *fs = opaque;
93 uint32_t rval;
94
95 rval = fs->regs[addr >> 2];
96 D(printf("%s %x=%x\n", __func__, addr, rval));
97 return rval;
98}
99
100static void pic_write(void *opaque, hwaddr addr,
101 uint64_t value, unsigned int size)
102{
103 struct etrax_pic *fs = opaque;
104 D(printf("%s addr=%x val=%x\n", __func__, addr, value));
105
106 if (addr == R_RW_MASK) {
107 fs->regs[R_RW_MASK] = value;
108 pic_update(fs);
109 }
110}
111
112static const MemoryRegionOps pic_ops = {
113 .read = pic_read,
114 .write = pic_write,
115 .endianness = DEVICE_NATIVE_ENDIAN,
116 .valid = {
117 .min_access_size = 4,
118 .max_access_size = 4
119 }
120};
121
122static void nmi_handler(void *opaque, int irq, int level)
123{
124 struct etrax_pic *fs = (void *)opaque;
125 uint32_t mask;
126
127 mask = 1 << irq;
128 if (level)
129 fs->regs[R_R_NMI] |= mask;
130 else
131 fs->regs[R_R_NMI] &= ~mask;
132
133 qemu_set_irq(fs->parent_nmi, !!fs->regs[R_R_NMI]);
134}
135
136static void irq_handler(void *opaque, int irq, int level)
137{
138 struct etrax_pic *fs = (void *)opaque;
139
140 if (irq >= 30) {
141 nmi_handler(opaque, irq, level);
142 return;
143 }
144
145 irq -= 1;
146 fs->regs[R_R_VECT] &= ~(1 << irq);
147 fs->regs[R_R_VECT] |= (!!level << irq);
148 pic_update(fs);
149}
150
151static void etraxfs_pic_init(Object *obj)
152{
153 DeviceState *dev = DEVICE(obj);
154 struct etrax_pic *s = ETRAX_FS_PIC(obj);
155 SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
156
157 qdev_init_gpio_in(dev, irq_handler, 32);
158 sysbus_init_irq(sbd, &s->parent_irq);
159 sysbus_init_irq(sbd, &s->parent_nmi);
160
161 memory_region_init_io(&s->mmio, obj, &pic_ops, s,
162 "etraxfs-pic", R_MAX * 4);
163 sysbus_init_mmio(sbd, &s->mmio);
164}
165
166static Property etraxfs_pic_properties[] = {
167 DEFINE_PROP_PTR("interrupt_vector", struct etrax_pic, interrupt_vector),
168 DEFINE_PROP_END_OF_LIST(),
169};
170
171static void etraxfs_pic_class_init(ObjectClass *klass, void *data)
172{
173 DeviceClass *dc = DEVICE_CLASS(klass);
174
175 dc->props = etraxfs_pic_properties;
176 /*
177 * Note: pointer property "interrupt_vector" may remain null, thus
178 * no need for dc->user_creatable = false;
179 */
180}
181
182static const TypeInfo etraxfs_pic_info = {
183 .name = TYPE_ETRAX_FS_PIC,
184 .parent = TYPE_SYS_BUS_DEVICE,
185 .instance_size = sizeof(struct etrax_pic),
186 .instance_init = etraxfs_pic_init,
187 .class_init = etraxfs_pic_class_init,
188};
189
190static void etraxfs_pic_register_types(void)
191{
192 type_register_static(&etraxfs_pic_info);
193}
194
195type_init(etraxfs_pic_register_types)
196